Pyrazole-1-carbothioamide as a Potent Precursor for Synthesis of Some New N-heterocycles of Potential Biological Activity

Herein, we reported the efficient synthesis of new azoles as bio-functional analogs, employing the easily obtainable N-acetyl-3,5-diphenyl-4,5-dihydro-1H-pyrazole-1-carbothioamide (1), as a versatile precursor. The structures of the newly synthesized compounds were elucidated based on their IR, H-1 NMR, and C-13 NMR mass spectral and elemental analysis. Furthermore, some selected compounds were evaluated in vitro for their antimicrobial activities. The preliminary bioassay results indicate that the majority of the tested compounds exhibited significant antimicrobial activity. Compounds 12, 11, 18, 30, 22, 3, and 2 were found to be the most potent against the tested microorganisms with minimum inhibitory concentration <= (12.25 mu g/mL), indicating that conjugates bearing thiazole moiety, as well as those with N-substituted electron-withdrawing groups, exhibited higher potency than the rest of other compounds.